| 摘要 |
Provided is a powerless wireless sensing device installed in a power facility to discover abnormality of the facility. The powerless wireless sensing device comprises: an inter-digital transducer (IDT) receiving a call signal, a call sign of which is page-modulated, and converting the call signal into a surface acoustic wave; a variable code setting unit setting a variable code; a phase modulation unit conducting phase modulation of the surface acoustic wave based on correlation between the call sign of the surface acoustic wave and the variable code; a transmission IDT conducting piezoelectric conversion of the phase-modulated surface acoustic wave into a response signal and transmitting the response signal; a light sensing unit sensing light generated by arc discharge and outputting a voltage corresponding to the light; and an impedance conversion unit connected to the variable code setting unit and setting the variable code based on the output voltage of the light sensing unit. The phase modulation unit outputs the phase-modulated surface acoustic wave if the call sign and the variable code are auto-correlated. |
